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51.
F. S. Babichev Yu. M. Volovenko A. G. Nemazanyi Bushra Nemaa 《Chemistry of Heterocyclic Compounds》1989,25(2):230-230
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 273–274, February, 1989. 相似文献
52.
M. S. Hundal Geeta Sood Parveen Kapoor S. S. Tandon 《Journal of chemical crystallography》1988,18(5):601-607
The title compound C18H18N2O2S is monoclinic with unit-cell dimensionsa=8.849(10),b=9.185(11),c=20.257(9) Å,=109.28(10)°. The space group isP21/c, withZ=4. Data were measured by photographic methods. The structure was solved by direct methods. A full-matrix least-squares refinement converged toR=0.10. All atoms except sulfur were assigned individual isotropic thermal parameters. The conformation of the thiadiazepine ring system is distorted boat shaped, as indicated by torsion angle studies. 相似文献
53.
Simple Organic Salts Having a Naphthalenediimide (NDI) Core Display Multifunctional Properties: Gelation,Anticancer and Semiconducting Properties 下载免费PDF全文
Following a supramolecular synthon rationale, a dicarboxylic acid derivative having a naphthalenediimide (NDI) core, namely, bis‐N‐carboxymethyl naphthalenediimide ( NDI‐G ), was reacted with n‐alkyl amines with varying alkyl chain lengths to generate a new series of primary ammonium dicarboxylate (PAD) salts. The majority of the salts (≈85 %) were found to gel various polar solvents. The gels were characterized by dynamic rheology and high‐resolution electron microscopy. Single‐crystal and powder X‐ray diffraction analyses were used to study the supramolecular synthon present in one of the gelator salts (i.e., S8 ). Charge‐transfer (CT)‐induced gelation with donor molecules such as anthracene methanol ( Ant ) and pyrene ( Py ) was also possible with S8 . The CT complex ( S8.Ant ) displayed anticancer activity as probed by cell migration assay on the highly aggresive breast cancer cell line MDA‐MB‐231 . The DMSO gel of S8.Ant also displayed semiconducting behavior. To the best of our knowledge, simple organic salts with an NDI core that display such mulitifunctional properties are hitherto unknown. 相似文献
54.
A series of mixed‐ligand‐based CdII/CoII coordination polymers (CPs) that were derived from two bis(pyridyl)–bis(amide) ligands, 4,4′‐oxybis(N‐(pyridin‐3‐yl)benzamide) ( LP ) and 4,4′‐oxybis(N‐(pyridin‐4‐yl)benzamide) ( LP1 ), and a variety of dicarboxylates isophthalates, terephthalates, 1,2‐carboxytranscinamates, and 1,3‐ and 1,4‐phenylene dicarboxylates were synthesized based on a rationale that they would occlude solvate guests inside their crystal lattice, thereby rendering these CPs suitable as metallogelators. The CPs were characterized by using single‐crystal X‐ray diffraction, elemental analysis, powder X‐ray diffraction (PXRD), FTIR spectroscopy, and thermogravimetric analysis (TGA). Structural analyses revealed that the majority of the CPs were lattice‐occluded molecular solids, which provided us with an opportunity to study their gelation behavior. We observed that, out of eight CPs that were tested, seven were able to produce metallogels. A thorough study of the rheological behavior of the metallogels was performed and CPG1 , CPG2 , CPG4 , and CPG5 were found to exhibit rheoreversible behavior, which was further confirmed by rheological experiments. Interestingly, ligand LP was found to form an aqueous gel, which was exploited to produce silver nanoparticles. 相似文献
55.
A simple precise method is described for the determination of isonicotinic acid hydrazide (isoniazid) alone, and in mixtures with aspirin, paracetamol and streptomycin, by reaction with vanillin in the Weisz ring-oven technique; 0.1–15 μg of isoniazid can be determined with errors of 2–2.7%. 相似文献
56.
Sengupta Arijit Deb Ashish Kumar Singha Gupta Nishesh Kumar Kumar Parveen Dasgupta Kinshuk Ali Sk. Musharaf 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):331-340
Journal of Radioanalytical and Nuclear Chemistry - Herein, sorption of pentavalent neptunium from aqueous acidic solution was carried out onto 1st and 2nd generation of poly(amidoamine) dendrimer... 相似文献
57.
Ameena Parveen Raghunandan Dashpande Shakeel Ahmed Aashis S. Roy 《Chemical Papers》2013,67(3):350-356
The polyaniline-PbO composites of various mass fractions were prepared by in situ polymerisation. The prepared samples were characterised by FTIR, and the dominant peaks confirmed the formation of polyaniline-PbO composites. The SEM study shows a granular agglomerated morphology, and increases with an increase in the lead oxide mass % in polyaniline. Direct current (DC) conductivity (σ DC) was studied as a function of temperature (T). From these studies, it was found that conductivity increased at higher temperatures due to the polarons hopping from one localised state to another. DSC studies reveal, the decrease in peak temperature from 273°C (pure PANI) to 169.2°C, 193.5°C, 218.4°C, 235.2°C, and 224.2°C, respectively for the various mass fractions (10 %, 30 %, 20 %, 40 %, and 50 %) of polyaniline-PbO composites. 相似文献
58.
Rehman Samiya Keefover-Ring Ken Haq Ihsan ul Dilshad Erum Khan Mohammad Imran Akhtar Nosheen Mirza Bushra 《Applied biochemistry and biotechnology》2019,188(3):893-895
Applied Biochemistry and Biotechnology - The original version of this article unfortunately contained a mistake in the image of Figure 1 and in Table 4. The corrected version of the figure... 相似文献
59.
60.
Phylligenine, together with quebrachitol, stigmasterol and two aporphine alkaloids--oxoputerine and liriodenine--were isolated from the twigs of Mitrephora vulpina C.E.C. Fisch. They were evaluated for their ability to inhibit platelet activating factor (PAF) receptor binding to rabbit platelets using 3H-PAF as a ligand and their antiplatelet aggregation effect in human whole blood induced by arachidonic acid (AA), collagen and adenosine diphosphate (ADP). Of all the compounds tested, phylligenin and quebrachitol exhibited potent and concentration-dependent inhibitory effects on PAF receptor binding, with IC(50) values of 13.1 and 42.2 μM, respectively. The IC(50) value of phylligenin was comparable to that of cedrol (10.2 μM), a potent PAF antagonist. Phylligenin also showed strong dose-dependent inhibitory activity on platelet aggregation induced by AA and ADP. 相似文献